Pathology specimens and their associated clinical data, archived in repositories of various configurations, represent a vast and underutilized mine of valuable resource. The emergence of the Internet and its related technology now-offers an opportunity to coordinate these valuable resources. Cost, logistical, and public policy issues make a centralized repository of specimens and/or specimen-related information unpalatable. In "Consented High-performance Indexing and Retrieval of Pathology Specimens" (CHIRPs) we propose an approach to a distributed specimen-informatics network, that will allow institutions to maintain local control of specimens, related identifiers and other sensitive information while safely sharing anonymized data across institutions. CHIRPs will support a novel peer-to-peer network where each site will announce their presence to others, and will distribute queries among themselves, in a manner similar to GnutellaNet. One key addition to the model is a method for secure authentication of clients and servers when needed, through the use of digital certificates. These major goals will be addressed: 1) Establishing a scalable Extensible Markup Language (XML) representation of specimen annotation that will support both a least common denominator access and an advanced query access to existing specimen information across multiple healthcare delivery and research institutions, 2) Formulating a taxonomy of patient consent that is part of the XML-based annotation, allowing for a balance between the advancement of biomedical knowledge and the protection of patient privacy, and 3) Developing a peer-to-peer distributed architecture for indexing and searching for specimens that leverages the Internet and the Web, and that minimizes the effort needed to participate in the Shared Pathology Informatics Network (SPIN). CHIRPs will be implemented and tested for its scalability across the Harvard/UCLA consortium, which joins two large academic medical centers, each with an established comprehensive cancer center, the Dana- Farber/Harvard Cancer Center and the Jonsson Comprehensive Cancer Center. The Harvard/UCLA consortium is composed of 9 member institutions representing 7 different pathology information systems and their associated archives containing millions of annotated specimens. The development and implementation of caws will provide a means to harness these existing valuable resources and a generalized platform to index and host specimen-related information prospectively to support future collaborations.